1. Technical Field
The present invention relates to a process for producing a pigment-containing curable resin solution composition, a pigment dispersed liquid, and the pigment-containing curable resin solution composition. This pigment-containing curable resin solution composition has excellent dispersion stability of pigment, and its cured film can be used preferably as, for example, the insulating protection film for a printed wiring board.
2. Background Art
A printed wiring board, for example, includes an insulating protection film covering circuit portions on a surface circuit patterns excluding connecting terminal portions. This insulating protection film (cured film) is usually colored green or blue. Therefore, the pigment-containing curable resin solution composition, which is obtained by dispersing pigment within a curable resin solution composition, is often used as a curable resin solution composition for the insulating protection film.
The patent documents 1 and 2 describe polyimide siloxane solution compositions as the curable resin solution composition for the insulating protection film. The patent document 1 describes that the polyimide siloxane solution composition may comprise pigment. However, no specific procedure is described how to achieve good dispersion stability of pigment in the polyimide siloxane solution composition.
The patent document 3 describes the polysiloxane modified with linear polyester comprising carbonate group or (meth)acryloyl group, and the document describes the use of the polysiloxane as an additive for irradiation curable coating. Whereas it is described that pigment may be added into the coating material, no specific procedure is described how to achieve good dispersion stability of pigment.
The patent document 4 describes polyaramid siloxane-based heat-resistant adhesive, and it is described that this modified polyimide siloxane may comprise a cross-linker and be used as a protection film. However, no specific procedure is described how to achieve good dispersion stability of pigment.